The invention also relates to a shoe manufactured with the assembly insole.
The shoe that uses the new insole can adapt, better than others, to being configured for activities which do not require a particular shock-absorbing effect.
According to known shoe manufacturing techniques, the assembly insole is used as a supporting element onto which the upper is assembled before applying the sole, substantially in order to close the “sack” designed to three-dimensionally wrap around the foot.
The assembly insole is a separate component with respect to the others that compose the shoe and utilizes clearly distinct principles and technology with respect to the others.
Therefore, from the constructive standpoint the shoe can be composed of two intermediate components: a sack-like one, which comprises the upper and the assembly insole, and one, the sole, which is applied below the sack.
Only in so-called “tubular” construction the sack of the upper is closed by applying the upper portion, known as vamp.
The application of the assembly insole to the upper, in structures which provide for it, is performed by means of adhesives or with stitches or other mixed systems.
In some constructive cases, the assembly insole is not present, since the upper is sewn and/or glued directly to the sole; in this case, the sole acts as an assembly insole.
The assembly insole must not be confused with the insole on which the foot rests, which is known as “hygienic insole” or “footbed” and has no structural function for the manufacture of the shoe.
There is only one case in which the assembly insole coincides with the footbed, and it is when one or more layers are not introduced, after assembly, in the shoe over the assembly insole and therefore under the foot of the user.
In these cases, the assembly insole acts as a footbed, since it is provided so that it is possible to close the upper on the side that is directed toward the sole (the footbed, due to how it is made and due to the materials used, instead can never perform the function of an assembly insole).
The assembly insole can be made of the most disparate materials and structures depending on the use for which the shoe is intended, but in any case must always be able to constitute a support for the upper and many times also for the sole, so that the shoe stays together.
The assembly insole can be reinforced by applying shanks and/or be made more flexible by means of cuts, holes or sections made of softer materials.
In many shoes, not only sports shoes, the sole assumes a merely protective or technical purpose, and therefore the assembly insole is assigned the task of keeping the shoe together and of bearing the weight of the user.
For example in cycling shoes, the sole is designed substantially to allow engagement or contact with the pedal; in soccer shoes, the sole must allow the application of studs, and in golf shoes it must allow to apply spikes.
In some very light shoes, lightweight and thin treads have the only purpose of protecting against wear the material arranged below the shoe, for example the hide of tubular moccasins.
Shoes are known which solve the problem of perspiration by perforating the sole and introducing special membranes which are impermeable to water and permeable to water vapor and allow breathing but prevent the penetration of water and/or moisture or foreign objects into the shoe.
In particular, a structure is known which replaces the central portion of the sole with a membrane which is supported by a protective net and by other layers in order to maximize the vapor-permeable (breathing) surface of the sole.
A similar solution is proposed by another invention which uses a membrane arranged inside the shoe, in the lining or in the assembly insole, with a layer of net or other vapor-permeable material arranged within the sole and capable only of protecting the membrane against blunt objects which might be trodden upon while walking.
These solutions allow to use soles composed of shock-absorbing layers and layers which are wear-resistant and antislip (tread).